Gerenciamento de borras oleosas provenientes de refinaria de petróleo

Abstract

The oily sludge wastes are composed of sediments (clay, silica and iron oxides) contaminated with oil, water and chemicals used in the processing of petroleum. The technologies applicable to oily sludges are landfills, incineration, co-processing in clinkerization furnaces, thermal plasma, thermal desorption, microwave liquefaction, centrifugation, destructive distillation, low-temperature conversion, incorporation in ceramic materials, development of impermeabilising materials, encapsulating, landfarming, biopiles, and bioreactors. This thesis aimed to developing a methodology for management of oily sludge generated in oil refining activity, taking into account physical and chemical characteristics of the waste, operating costs and environmental impacts of technologies. The environmental impacts data were obtained by consulting experts in the field, which attributed concepts to the impacts of: water use, energy use, wastewater generation, solid waste generation, risk of contamination of groundwater and air pollution. These concepts were converted to numerical values by simplified method Fuzzy Multi-criteria Decision Analysis (MCDA).We observed four kinds of oily sludges in accordance with local generation in refining units. The mapping of operating costs and environmental impacts of technology allowed us to develop a heuristic choice of treatment for each type of oily sludge. This thesis presents a case study of an oil refinery that allowed us to validate the heuristics developed. The results showed that even with low operating costs, many technologies lose competitiveness because they have adverse environmental impacts. According to the heuristic technologies listed the types of oily sludge are oily sludge with low levels of oils and greases for conversion at low temperature, oil and water for landfarming, and oily sludge with levels oils and greases and kind of the oil and sediments by encapsulation.